Featured Research

from universities, journals, and other organizations

Weird 'Engine Of The Reef' Revealed

Date:
August 31, 2007
Source:
ARC Centre of Excellence in Coral Reef Studies
Summary:
A team of coral researchers has taken a major stride towards revealing the workings of the mysterious 'engine' that drives Australia's Great Barrier Reef, and corals the world over. The science has critical importance in understanding why coral reefs bleach and die, how they respond to climate change -- and how that might affect humanity, they say.

What processes allow coral to build these amazing structures?
Credit: Image courtesy of ARC Centre of Excellence in Coral Reef Studies

A team of coral researchers has taken a major stride towards revealing the workings of the mysterious ‘engine’ that drives Australia’s Great Barrier Reef, and corals the world over.

The science has critical importance in understanding why coral reefs bleach and die, how they respond to climate change – and how that might affect humanity, they say.

Scientists at the ARC Centre of Excellence for Coral Reef Studies, James Cook University and the University of Queensland have compiled the world’s first detailed gene expression library for Symbiodinium, the microscopic algae that feed the corals – and so provide the primary energy source for the entire Reef.

“Symbiodinium uses sunlight to convert CO2 into carbohydrates for the corals to feed on. At the same time there’s evidence the corals control its output, suggesting that they are farming their captive plants” Professor David Yellowlees explains.

“But these microscopic algae are quite weird and unlike any other lifeform. They have different photosynthetic machinery from all other light harvesting organisms. They have 100 times more DNA than we do and we have no idea why such a small organism needs so much. They really are like no other living creature we know.

This is echoed by team member Prof Ove Hoegh-Guldberg who comments it is ‘like no other organism on planet’, jokingly labeling it “like an alien”.

This strange beast not only rules the fate of the world’s coral reefs – it also plays a significant role in soaking up carbon dioxide from the atmosphere, turning it into nourishment for the corals and powering calcification. Its decline would not only kill the reefs but accelerate CO2 buildup.

Dr Bill Leggat says the team has focused particularly on understanding the biochemical relationship between Symbiodinium and corals when they are stressed by heat, light, increased CO2 levels and pollutants from land run-off.

These stressful conditions cause corals to ‘bleach’ by expelling the Symbiodinium and – if they do not recover them within a few days – the corals die. Large-scale bleaching struck half of the Great Barrier Reef in 2002, and eight major bleaching episodes have been reported worldwide in the last 30 years due to warming sea water.

“Our aim is to identify the genes that make the symbiotic plants susceptible to these stresses, and lead to the coral expelling them,” Dr Leggat says.

In experiments at Heron Island Research Station they exposed corals to various stresses associated with climate change and then analysed the gene composition in the symbiotic algae. Another team analysed the effects in corals.

Working together and using the powerful micro-array technology, they hope to assemble a picture of the ‘chemical conversation’ that goes on between the corals and its symbiotic plants that leads to a breakdown in the relationship, a divorce - and the corals starving themselves to death.

“An example of the challenge we face is the gene which is expressed the most when Symbiodinium is stressed. It’s obviously important - but at this stage we have no idea what it does. It is even stranger when you consider that this gene was originally acquired from a bacterium” Prof Yellowlees says.

So far the team has identified about 4500 genes in Symbiodinium, compiling them into the world’s first gene expression library for this symbiotic organism. It is hoped this will have value for understanding other symbiotic relationships in nature.

Symbiodinium is part of a larger group of organisms called dinoflagellates, responsible for events like red tides and ciguatera poisoning. Together, the dinoflagellates process about one third of all CO2 entering the oceans – and are thus vital players in helping to remove CO2 from the atmosphere. Understanding how they function will help fill in one of the critical gaps in our understanding of climate change – how much CO2 the oceans can trap and how this will affect ultimate climate change.

Details of the team’s research findings will be published in the Journal of Phycology later this year.


Story Source:

The above story is based on materials provided by ARC Centre of Excellence in Coral Reef Studies. Note: Materials may be edited for content and length.


Cite This Page:

ARC Centre of Excellence in Coral Reef Studies. "Weird 'Engine Of The Reef' Revealed." ScienceDaily. ScienceDaily, 31 August 2007. <www.sciencedaily.com/releases/2007/08/070830165013.htm>.
ARC Centre of Excellence in Coral Reef Studies. (2007, August 31). Weird 'Engine Of The Reef' Revealed. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2007/08/070830165013.htm
ARC Centre of Excellence in Coral Reef Studies. "Weird 'Engine Of The Reef' Revealed." ScienceDaily. www.sciencedaily.com/releases/2007/08/070830165013.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com
Amid Drought, UCLA Sees Only Water

Amid Drought, UCLA Sees Only Water

AP (July 30, 2014) A ruptured 93-year-old water main left the UCLA campus awash in 8 million gallons of water in the middle of California's worst drought in decades. (July 30) Video provided by AP
Powered by NewsLook.com
In Virginia, the Rise of a New Space Coast

In Virginia, the Rise of a New Space Coast

AP (July 30, 2014) Every summer, tourists make the pilgrimage to Chincoteague Island, Va. to see wild ponies cross the Assateague Channel. But, it's the rockets sending to supplies to the International Space Station that are making this a year-round destination. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

    Environment News

    Technology News



      Save/Print:
      Share:

      Free Subscriptions


      Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

      Get Social & Mobile


      Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

      Have Feedback?


      Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
      Mobile: iPhone Android Web
      Follow: Facebook Twitter Google+
      Subscribe: RSS Feeds Email Newsletters
      Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins